Gloria Mark, Chancellor’s Professor of Informatics at the University of California Irvine, has tracked attention spans on screens for two decades. In 2004, people averaged two and a half minutes on any screen before switching tasks. By 2016, that had fallen to 47 seconds. This is frequently cited as evidence that screens inherently fragment attention. But look closer at what Mark’s research actually shows. The fragmentation correlates not with screens in general but with specific design patterns: notification systems, variable reward schedules, infinite scroll. These are choices made by specific companies for specific economic reasons. They are not inherent properties of the medium. Peer-reviewed research demonstrates that social media platforms exploit variable reward schedules, the same psychological mechanisms that make gambling addictive. Users don’t know what they’ll find when they open an app; they might see hundreds of likes or nothing at all. This unpredictability acts as a powerful reinforcement signal (often discussed via dopamine ‘reward prediction error’ mechanisms), keeping people checking habitually. This isn’t because screens are inherently attention-destroying. It’s because the dominant platforms have been deliberately engineered to fragment attention in service of advertising revenue.